Machine for automatically opening square-bottom paper bags



Nov. 8, 1932. x. DAMBACHER ,3 MACHINE FOR AUTOMATICALLY OPENING SQUARE BOTTOM PAPER BAGS Filed March a, 19321 2 Sheets-Sheet 1 O a; 119 34 I 15 0,- 4 r": 0 pl" EL i o a? m g r I 395 I'HH} rm .1?

I XIDQW) INVQN TOR V NM 8, 1932. DAMBA HER 1,886,376

MACHINE FOR AUTOMATICALLY OPENING SQUARE BOTTOM PAPER BAGS Filed March 8, 1932 2 Sheets-Sheet 2 l g i 27 i 42 127g l 197; ,1 ,9

f 29 80 f, I'-

hive/ 7212 Patented Nov. 8, 1932 UNITED STATES PATENT OFFICE XAVER DAMBAGHER, OF LENGERICH IN WESTPHALIA, GERMANY, ASSIGNOR TO THE PIE]! WINDMOLLEB & HOLSCHER, G. M. B. 131., OF LENGERICH,WESTPHALIA, GERMANY MACHINE FOB AUTOMATICALLY OPENING SQUARE-BOTTOM PAPER BAGS Application filed March 8, 1932. Serial No. 597,540.

This invention relates to an improvement in a machine for the automatic opening of square bottom paper bags especially, although not exclusively, those with side tucks, of which the following is a specification.

This invention relates to a machine for automatically opening fiat folded square bottom paper bags rendering them ready to be filled by self-acting filling machines (not forming an object of this invention) for arm ticles usually in the form of grains or powders such as legumens, sugar, salt, cofl'ee, cocoa or the like.

One of the main objects of this invention is to. influence the bag which, in its manufacture, assumes a flat and plain compressed form with the square bottom appressed to the side, into which form it tends to return by its elasticity, in such a way as to spread it out from its compressed form by the action of the movable fingers cooperating with the upper edge of the bag and opening plungers into the shape suitable for filling.

The accompanying drawings represent a suitable form for carrying out this invention, omitting such parts which are unnecessary for its elucidation Fig. 1 is a side view of the machine, Fig; 2 is a front view seen from the left in Fig. 1 partly in section and omitting driving parts,

Fig. 3 is a partial plan view, Fig. 4 shows the plunger fully introduced into the bag.

F is the framework of the machine with a table T for carrying and supporting the cooperating parts, including the main driving shaft M with a number of cam discs such as 10, 11, 12 acting by means of guide rollers on levers pivotallysupported at the framework, which rollers are continuously held in contact with the said cam discs by any suitable well-known means, such as tension springs. Above the table T a reception and guide basket 13 of segmental form is fixed by means of a support 14, holding a pile of flatly compressed square bottom bags 15 of well-known design in that form in which they leave the paper bag machine. A heavy plate 16 by its weight keeps the bags lightly compressed and tends to drive them to the delivery end where the foremost bag is stopped by small stops 80. A table 17 is, as shown, arranged at the delivery side of the basket 13. Above the table and in front of the delivery end of thebasket 13 means for opening or spreading the bags are arranged, comprising fingers 18, 19 and a pair of fingers 20 preferably consisting of flat resilient material (sheet metal springs), a lever cooperating with the finger 18 and forming tongs with the said finger, and an opening plunger 22, means being provided for guiding and operating these parts. These operating means comprise a drive, preferably a cam shaft M situated under the main table T. In a preferred constructional form means are provided for supplying compressed air to the plunger 22. v The fingers 18, 19 and the lever 21 pressed against the finger 18 by a spring 23 are supported by the arms 24 and 25 of slides 26, 27 which are movable along a guide way 28 arranged parallel to the table T. This guide way 28 is supported by a rod 30 which may be reciprocated up and down in a supporting sleeve 29 upon the table T, a roller 31 arranged at the lowerend of this rod 30, as diagrammatically shown in Fig. 2, being in continuous contact with a cam disc 32 of shaft M. In order to avoid unclearnesses by a multiplicity of lines this cam disc is omitted in Fig. 1. v

The slides 26, 27 are connected by links 33, 34 with the upper arms of double-armed 1evers 36, 37 pivotally supported upon the table T at 35. The lower ends of these levers are oscillated by. cam discs 40, 41 of the main shaft M, being in driving connection with the said levers by any usual means, such as pivotal levers, contact rollers and connecting levers. Of thesemeans for the sakeof clearness only the-levers 38, 39 have in part been 90 shown in Fig. 1, as these means for oscillating levers by means of cam discs are well known in the art. Similar pivotal levers with Contact rollers are shown in Fig. 1 for driving other parts of the machine and will be described more fully below. The cam discs 40, 41 are so'shaped and arranged as to be able to impart to the slides 26, 27 a common movement parallel to the table in one direction or another, as well as an opposite movement, towards each other or away from each other along the guide 28.

The fingers 20 are fixed at the end of the levers 42 which are fastened on cylindrical rods 43 situated at both sides of the basket 13 and table 17, and may be rotated as well as axially reciprocated in sleeves 44 supported by the table T. At the lower ends of these rods 43 below the table T, levers 45, 46 are provided which interengage in the middle between the rods 43 by means of toothed seg ments 47. A tension spring 48 being fixed at arms and 46 of these two levers tries to pull the arms towards each other. The lever 46, 46' has another arm 46" extending substantially in the same direction which is provided with a toothed segment and supporting at its end a contact roller 49 which, on account of the action of the spring 48, is always kept in contact with the end of a lever 50 pivotally supported at 51 of the frame F. A roller 52 supported by this lever 50 is by means of a tension spring 53 always kept in contact with the above mentioned cam disc 10 of the shaft M.

The hubs of the levers 45, 46 at the lower ends of the rods 43 are provided with ringgrooves 54 which are enga ed by pins 55 at the ends of a crank lever 5 pivotally supported at 56 of the table T. A spring 58 tries to turn the lever in a clockwise direction and holds a roller 59 supported by the lever in contact with the cam disc 11 of the main shaft M.

The plunger 22 is carried by a vertical rod 60 in the example constructed as a tube, which is supported by an arm 61 which may slide up and down in sleeves 63, 64 of a rod 62 supported by the table T, and a frame 65 respectively. A link 66 engaging the lower end of the rod 62 connects it with the end of the crank lever 68 supported at 67 in the frame F, a tension spring 69 engaging this lever tries to turn this lever 68 in a clockwise.

direction (in Fig. 1) and a. lever 72 connects the said lever 68 with another lever pivotally supported at the table T at 71. This lever again is by means of a roller 73 in cooperation with the cam disc 12 of the main shaft M.

The manner of o eration of the device so far described is as ollows:

At the beginning of the Working period the ide way 28 is raised and the slides 26, 2 approach each other and move to the right in Fig. 1 close to the vertical plane in which the stops 80 are arranged. The lower ends of the fingers 18, 19 are then raised .so far as to pass the usual and known fingernotch 74 (see Fig. 2) in one of the walls of the foremost bag 15, which touches the stops 80, and to press the other wall (not provided with a notch, as 74) slightly backwards towards the plate 16, so that the bag is slightly opened. At this moment the slides 26, 27 approach each other by the cam discs 40, 41 and the cooperating train of levers, so that the fingers 18, 19 are in contact with each other. At the same time the arm 21 acted upon by the spring 23 and forming tongs with finger 18 has met a stop 77 at the guide way 28 in such a way that it is pressed away from finger18, the tongs thus being opened.

Now by the cam 32, the rod 30 with the guide way 28, the slides 26, 27 and fingers 18, 19 are lowered so that the fingers enter the bag. At the same time cams 40, 41 move the slides 26, 27 with the fingers to the left. At the beginning of this movement the tongs 18, 21 close as the lever 21 leaves the stop 77. The tongs take the bag 15 with them, the edges of the bag passing the stops 80. During their movement to the left in Fig. 1 the slides 26, 27 are drawn asunder by the cam discs 40, 41 into the position shown in Fig. 1, so that the two sides of the bag situated parallel to the front level or delivery end of the pile of'bags are separated.

Now the fingers 20 which also have been raised at the beginning of the workin period and approach each other are lowere by the cam 11, whereas the cam disc 10, by means of lever 50, crank levers 45, 26, spring 48 and segments 47, oppositely rotates the rods 45, 46 so that the said levers (see Figs. 2 and 3) enter the bag and open and spread out the folded tucks of the bag. Now the upper or open edge of the bag is drawn open to a rectangle.

Immediately following this, the plunger 22 islowered under action of the cam disc 12 and cooperating parts such as 62, 66, 68, 69, 70, 72. The plunger 22 having a crosssection similar to the inner section of the bag when filled is lowered close to the bottom of bag 15 (see Fig. 4 and close to the surface of the table 17. y this action the square bottom of the bag is opened in "such a way that it cannot spring together again. In that moment in which the plunger has been brought to its lowermost position the fingers 18, 19 and the tongs 18, 21 are by the described parts acted upon by the cam discs returned again into their initial position so that they can grip a new bag-and bring it below the rising plunger 22, so that this can immediately be lowered again and can spread a new delivered bag. The speed of the operation is increased hereby. During the lifting of the plunger 22 under the action of the described operation, the bag 15 having been spread out can be released and conveyed away by any well known means,

not shown, for further use, whereupon the ldescribed operation repeats with the next The spreading effect of the plunger 22 may be assisted by special spreading means which come into action when the plunger has approached the bottom of the bag (as shown in Fig. 4). E. g. as shown the tube 60 carrying the plunger 22 may be connected by a hose 78 and a valve 76 periodically opened by a cam 7 5 of the shaft M with a source of compressed air (not shown) so that at the right moment compressed air entering the plunger 22 is delivered by means of bores 79 into the room between plunger and bottom of the bag, as indicated by small arrows in Fig. 4, so that an elastic and complete spreading of the bag and an easy return movement of the plunger out of the bag is ensured.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is 2-- 1. In a machine for automatically spreading folded square bottom paper bags, means for supporting a pile 'of bags in a flat condition, means to catch one bag after the other from the delivery end of the said pile, means for separating the side walls of the said bag lying close together, the said means comprising thin elastic fingers, means to introduce the said fingers into the bag in a direction parallel to the plane of the said walls, means to separate them after they have been introduced, a second set of spreading fingers arranged to enter and spread the open end of the said bag in a direction vertical to the spreading action of the said first fingers, a plunger arranged above the said paper bag when spread out at its open edge by the said sets of fingers, means to lower the said plunger into the opened edge of the said bag and close to the bottom of it, and means to return the plunger and fingers into their initial position leaving the paper bag in a spread condition.

2. In a machine for automatically spreading folded square bottom paper bags, a segment-shaped basket for supporting a pile of bags in a flat condition having a delivery and a feedin end, a plate at the feeding end and elastic stops at the delivery end of the said basket, thin elastic fingers arranged before the delivery end, means to move the said fingers in such a way that they approach each other and enter the open end of the first of the said bags retained by the said stops, an elastic lever cooperating with one of the said fingers and means to control it so as to automatically catch the outer side of the front wall of the said bag after the said fingers have been introduced, means to spread out the fingers from the delivery end of the said basket and to separate them from each other for a predetermined way, a second set of spreading fingers arranged to enter and spread the open end of the said bag in a direction vertical to the spreading action of the said first ingers, a plunger arranged above the said paper bag when spread out at its open edge by the said sets of fingers, means to lower the said plunger into the opened edge of the said bag and close to the bottom of it, and means to return the plungers and fingers into their initial position leaving the paper bag in a spread condition.

3. In a machine for automatically spreading folded square bottom paper bags, a segment-shaped basket for supporting a pile of bags in a flat condition having a delivery and a feeding end, a plate at the feeding end and elastic stops at the delivery end of the said basket, thin elastic fingers arranged before the delivery end, means to move the said fingers in such a way that they approach each other and enter the open end of the first of the said bags retained by the said stops, an elastic lever cooperating with one of the said fingers and means to control it so as to automatically catch the outer side of the front wall of the said bag after the said fingers have been introduced, means to spread out the fingers from the delivery end of the said basket and to separate them from each other for a predetermined way, a second set of spreading fingers arranged to enter and spread the open end of the said bag in a direction vertical to the spreading action of the said first fingers, a plunger arranged above the said paper bag when spread out at its open edge of the said sets of fingers, means to lower the said plunger into the opened edge of the said bag and close to the bottom of it, spreading means at the said plunger, means to automatically bring them into action after the plunger has approached the bottom of the bag and means to return the plunger and fingers into their initial position leaving the paper bag in a spread condition.

4. In a machine for automatically spreading folded square bottom paper bags, a segment-shaped basket for supportin a pile of bags in a'fiat condition having a de ivery and a feeding end, a plate at the feeding endand elastic stops at the delivery end of the said basket, thin elastic fingers arranged before the delivery end,.means to move the said fingers in such a way that they approach each other and enter the open end-of the first of the said bags retained by the said stops, an elastic lever cooperating with one of the said fingers and means to control it so as to automatically catch the outer side of the front wall of the said bag'after the said fingers have been introduced, means to spread out the fingers from the delivery end of the said basket and to separate them from each other for a predetermined Way, a second set of spreading fingers arranged to enter and spread the open end of the said bag in a direction vertical to the spreadin action of the said first fingers, a plunger arranged above the said paper bag when spread out at its open edge by the said sets of fingers, means to lower the said plunger into the opened edge of the said bagand close to the bottom of it, openings in the lower end of the said plunger, means to automatically connect the said openings with a pressure pipe when the said plunger has approached to the bottom of the bag and means to return the plunger and fingers into their initial position, leaving the paper bag a spread condition.

5. In a machine for automatically spreading folded square bottom paper bags, means for supporting a pile of bags in a fiat condition, means to catch one bag after the other from the delivery end of the said pile, means for separating the side walls of the said'bag lying close together, the said means comprising thin elastic fingers, means to introduce the said fingers into the bag in a direction parallel to the plane of the said Walls, means to separate them after they have been introduced, a second set of spreading fingers arranged to enter and spread the open end of the said bag in a direction vertical to the spreading action of the said first fingers, a plunger arranged above the said paper ba when spread out at its open edge by the sai sets of fingers, means to lower the said plunger into the opened ed e of the said bag and close to the bottom 0 it, and means to return the plunger and fingers into their initial position leaving the paper bag in a .spread condition, the said means for controlling the said fingers and plunger comprising one common shaft with cam discs for creating the different operative movements. 6. In a machine for automatically spreading folded square bottom paper bags, means for supporting a pile of bags in a flat condition, means to catch one bag after the other from the delivery end of the said pile, means for separating the side walls of the said bag lying close together, the said means comprising thin elastic fingers, means to introduce the said fingers into the bag in a direction parallel to the plane of the said walls, means to separate them after they have been intro duced, a second set of spreading fingers arranged to enter and spread the open end of the said bag in adirection vertical to the spreading action of the said firstfingers, a plunger arranged above the said paper bag when spread out at its open edge by the said sets of fingers, means to lower the said plunger into the opened edge of the said bag and close to the bottom of it, means to release and return the said first set of fingers so as to catch a further bag as soon as the said plunger has been brought to its lowermost position, means to lift the plunger again leaving the bag in its spread condition and means to convey the said set of fingers with the caught bag towards the plunger during the said lifting movement of the plunger and means to lower the plunger again as soon as the bag has arrived below it.

XAVER DAMBACHER. 

